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Alpine Halo R2-Series Dual 12" Voice Coil 4-Ohm Loaded Subwoofer Enclosure Black R2-SB12V - Best Buy
Universal Car Stereo Slotted S Port Single 10" Alpine Bundle Type R R-W10D4 Sub Box Enclosure with Harmony HA-A800.1 Amplifier & 4GA Amp Kit - Walmart.com
Alpine 12 Inch Bass Line Subwoofer (W12S4) | SK Customs Car Audio & Home Theater | Atlanta | Norcross | Duluth | John's Creek
Alpine SWS-12D4 12 1500 Watt Car Subwoofer + Vented Sub Enclosure Box | Audio Savings